As is well known, short-distance, or residual-distance, recording in motor vehicles is used for analyzing the last distance traveled before a stop, possibly a stop which is caused by a collision, in an improved manner in comparison with tachograph charts. A wide range of recording principles are already known for devices of this type such as, for example, principles which enable immediate examination of the recordings, as well as those in which speed values are generally written into an electronic storage, continuously in a determined clock cycle as data records, sometimes together with other data, the least current data records being erased.
Of course, in relation to speed checks or an evaluation of an accident when the vehicle is stopped, such a device may continue to store zero speed values which are generated in a clocked manner only for a limited period of time sufficient for reliably detecting a stationary state. Accordingly, a known storage process marks the restarting of the vehicle by entering the starting time in the respective storage.
On the other hand, special accident recording devices are known in which accident data are determined, preferably by means of acceleration sensors, and stored for a relatively brief period, in a time-based manner, wherein additional information which concerns, for example, brake actuation, blinker operation and illumination, is compiled as an interpretation aid. Such a device permanently stores the accident data when the vehicle actually undergoes accelerations beyond the range of possible accelerations which are brought about by the nature of the road and the driving dynamics, i.e. in the event of genuine impacts caused by traffic accidents. In this way, the processor capacity and storage space can be confined to authentic accident situations.
Recordings made by devices of the first group can provide a certain support for recording and interpreting accidents in that the speed curve, which precedes the stopping of the vehicle, is analyzed on the spot and status data, which has been compiled such as "brakes applied", "blinker on" and the like, can be taken into account regardless of whether or not the vehicle has undergone an impact resulting from an accident. However, the actual reaction of the driver, the driving situations which resulted neither in a stopping of the vehicle nor in a collision, or hit-and-run situations, cannot be detected because these recordings are overwritten when the vehicle resumes driving. The same can also be said of the devices, which exclusively record collisions. While these devices enable an exact analysis of the events which precede and which follow an accident, this analysis can only be undertaken by experts. Also, the cost of such devices generally exceeds the acceptable limits for monitoring devices, which are not required by law, especially since they are used relatively rarely or not at all for the entire operating life of a vehicle. On the other hand, the first group of devices can be used much more frequently, namely, such as for traffic checks.